It may be the only part of the US-Russia relationship that actually works. The new strategic arms treaty or SMART, has been in place for just over four years and has already made substantial cuts to the nuclear arsenal of both sides. Barack Obama's chief negotiator on the treaty is Rose Gottemoeller, under secretary of state for arms control and international security.

Thousands of Iraqi forces begin surrounding Islamic State fighters in Tikrit and nearby towns on the second day of Iraq's biggest offensive yet against a stronghold of the radical Sunni Islamist militants.

Israeli prime minister Benjamin Netanyahu warns the United States that the nuclear deal it is negotiating with Iran could threaten Israel's survival and insists he has a "moral obligation" to speak up about deep differences with president Barack Obama on the issue.

Newly leaked spy cables, obtained by Al Jazeera and the Guardian, show a conflict between Israeli prime minister Benjamin Netanyahu and his own country's spy agency, Mossad, over Iran's development of nuclear weapons.

Syrian president Bashar al-Assad says third parties, including Iraq, are conveying information to Damascus about the US-led campaign of air strikes against the Islamic State (IS) militant group in Syria.